No abstract available

[en] The work performed from May 1980 through March 1981 is described. EUV diagnostic studies have been performed at the Alcator A, Alcator C and TFR 600 tokamaks and on TMX. The central molybdenum concentration in Alcator C has been shown to be much lower than that in Alcator A. Impurity concentration and radiative power losses have been determined in the center cell of TMX. A grazing incidence spectrograph with 1024 detector elements is under construction

No abstract available

[en] A comprehensive program to develop extreme ultraviolet and soft x-ray diagnostics for magnetically confined plasmas is described. An instrument for measuring the location and distribution of impurities near the plasma core with approx. 5 ms time resolution is under development. The results of evaluation tests for other new spectroscopic diagnostics on plasma devices in the DOE laboratories are described. Supporting laboratory studies and ionic structure calculations are also discussed

No abstract available

[en] The work performed from mid-January 1979 through 1980 is described. EUV diagnostic studies have been performed at the Alcator A and C Tokamaks, and on TMX. A toroidal asymmetry has been found in the low density phase of Alcator A. The confinement time of impurities has been measured on Alcator A. Impurity concentrations in the center cell of TMX have been studied using EUV spectroscopic techniques. A time resolving spectrograph with 1024 detector elements is essentially complete

[en] The results of the research program at this laboratory from mid February 1976 until January 31, 1977, are described. The four major research areas of the program: diagnostic studies of magnetically confined high temperature plasmas, supporting laboratory studies, theoretical studies of highly ionized atoms, and instrument development are discussed. Spatially resolved ultraviolet measurements on Elmo Bumpy Torus have determined impurity confinement times. The measured oxygen densities and fluxes are being determined at Alcator; the spectroscopic studies show that hydrogen discharges in this tokamak have an effective Z close to one. A laboratory study of the Penning discharge between 100 and 300 A shows that it is a bright source for evaluation of EUV diagnostic instrumentation. Design of a multispatial element spectrometer system is complete and construction has begun. A spectrophotometer compatible with both types of facilities is available for absolute intensity calibration transfer from the NBS SURF II facility to ERDA plasma facilities. Computer programs needed for relativistic calculation of transition probabilities and wavelengths have been completed and applied to calculations in the Li, Be, Ar, and K isoelectronic sequences

[en] This chapter demonstrates that relativity in a many-body system necessarily implies the use of quantum electrodynamics (QED). Discusses the two-electron Dirac equation; some approaches to relativistic many-body calculations; and the accuracy of the calculations. Points out that most of the methods which have been used to study many body systems nonrelativistically have been extended so that they may be used for relativistic studies. Concludes that the major difficulty in relativistic many body calculations lies not in the ''relativistic'' aspect, but rather in the ''many-body'' part

[en] Spatial scans of Alcator Tokamak have led to a more direct determination of the oxygen and nitrogen concentrations. These scans have also shown that grad B and curvature drifts are significant transport mechanisms in this device. Spatial scans of Elmo Bumpy Torus from both the top and the side have produced two dimensional plots of the impurity concentrations. Preliminary results from 2XIIB show that oxygen is the dominant impurity; nitrogen, carbon, and titanium are also present. The Spatial Imaging Detector System is discussed; construction is complete and it is being prepared for installation on a plasma machine. EUV photometric calibration techiques at this laboratory are described. The accuracy and stability of this calibration is discussed. Theoretical calculations of relativistic transition rates and energies have continued, and studies of electron-impact ionization and excitation cross sections have begun

[en] The report discusses the four major research areas of this program: diagnostic studies of CTR plasmas, laboratory spectroscopy and calibration at short wavelengths, theoretical computation of transition probabilities for highly ionized atoms, and instrument development for short wavelength studies of CTR devices. Using existing instruments, diagnostic studies are under way at Versator and Elmo Bumpy Torus. A facility has been completed for the sensitivity calibration of spectrometers down to 300 A as complete units. The development of computer programs necessary for transition probability calculations is ninety percent complete. An f/20 forty cm focal length concave grating spectrometer has been constructed utilizing very high vacuum techniques to reduce contamination of plasma devices and calibration sources such as SURF II at NBS. New designs for grazing incidence monochromators have been developed